简介：Anincubationexperimentwascarriedoutinlaboratorytostudytheeffectoftemperature,moisture,phosphorus,organicmatter,croppingandpreviouselementalsulfurapplicationonelementalsulfuroxidationinfourselectedsoils,fluvo-aquicsoil,blacksoil,yellow-brownsoilandredsoil,Inallthesoilstested,sulfuroxidationratewasinfluencedbytemperatureandthetemperaturecoefficient(Q10)valuesattherangefrom10to30℃were4.41,,6.19and3.71forthefoursoils,respectively.Therateofsulfuroxidationwasparabolicallyrelatedtosoilwatercontent.Theoptimummoisturecontentforthemaximumoxiationratewasdifferentamongsoils,Phosphorusincreasedtheoxidationrateofelementalsulfurby57.7%,33.1%,21.7%and26.4%fortheabovefoursoils,respectively,comparedwiththecontrol(nophosphorusapplied).Organicmaterialofcornstrawwhichwasgoundandpassedthrougha0.5-mmsievealsoincreasedthoxidationrateofelementalsulfurinthefoursoilsby59.8%,7.8%,39.2%and540.4%,respectively.Elementalsulfurwhichwasappliedpreviouslytosoilssignificantlyenhancedtheoxidationofelementalsulfursubsequentlyaddedandincreasedsulfur-oxidizingpopulationssuchasautotrophicelementalsulfuroxidizerswithpHoptimum6.8,autotrophicthiosufateoxidizerswithpHoptimum6.8,heterotrophicthiosulfateoxidizersandheterotrophicsulfateproducers.Croppinghadlittleeffectonelementalsulfur-oxidizingpotentialityofsoils.

简介：Methaneoxidationbypaddysoilsinaclosedsystemcouldbesimulatedbytheequationx=k1xo/(k1+k2x0)exp(k2t)-k2x0wherex0andxaretheCH4concentrationsattimezeroandt,respectively;k1andk2areconstantsrelatedtotheconstantoffirst-order-kinetics.AccordingtotheequationthechangeofsoilabilitytooxidizeCH4couldbeestimatedbytheequationAc=k2/k1(x0-x)x0k2/k1-1.TheresultsshowedthatthesoilabilitytooxidizeCH4varied,dependingontheinitialCH4concentration.HighinitialCH4concentrationstimulatedsoilabilitytoconsumeCH4,whilelowconcentrationdepressedtheablility.Thischaracteristicofpaddysoilseemedtobeofconsiderablesignificancetoself-adjustingCH4emissionfromfloodedricefieldsifthereexistoxicmicrositesinthesoil.

简介：NexttoCO2,methane(CH4)isthesecondimportantcontributortoglobalwarmingintheatmosphereandglobalatmosphericCH4budgetdependsonbothCH4sourcesandsinks.UnsaturatedsoilisknownasauniquesinkforatmosphericCH4interrestrialecosystem.ManycomparisonstudiesprovedthatforestsoilhadthebiggestcapacityofoxidizingatmosphericCH4invariousunsaturatedsoils.However,uptonow,thereisnotanoverallreviewintheaspectofatmosphericCH4oxidation(consumption)inforestsoil.ThispaperanalyzedadvancesofstudiesonthemechanismofatmosphericCH4oxidation,andrelatednaturalfactors(Soilphysicalandchemicalcharacters,temperatureandmoisture,ambientmaingreenhousegasesconcentrations,treespecies,andforestfire)andanthropogenicfactors(forestclear-cuttingandthinning,fertilization,exogenousaluminumsaltsandatmosphericdeposition,addingbiocides,andswitchofforestlanduse)inforestsoils.ItwasbelievedthatCH4consumptionratebyforestsoilwaslimitedbydiffusionandsensitivetochangesinwaterstatusandtemperatureofsoil.CH4oxidationwasalsoparticularlysensitivetosoilC/N,AmbientCO2,CH4andN2Oconcentrations,treespeciesandforestfire.Inmostcases,anthropogenicdisturbanceswilldecreaseatmosphericCH4oxidation,thusresultingintheelevatingofatmosphericCH4.Finally,theauthorpointedoutthatourknowledgeofatmosphericCH4oxidation(consumption)inforestsoilwasinsufficient.InordertoevaluatethecontributionofforestsoilstoatmosphericCH4oxidationandtheroleofforestplayedintheprocessofglobalenvironmentalchange,andtoforecastthetrendsofglobalwarmingexactly,moreresearchersneedtostudiesfurtheronCH4oxidationinvariousforestsoilsofdifferentareas.

简介：Effectsofnitrogenfertilizer,soilmostureandtemperatureandtemperatureonmethaneoxidationinpaddysoilwereinvestigatedunderlaboratoryconditions.Additionof0.05gNkg^-1soilasNH4ClstronglyinhibitedmethaneoxidationandadditionofthesamerateofKClalsoinhibitedtheoxidationbutwithmoreslighteffect,suggestingthattheinhibitoryeffectwaspartlycausedbyincreaseinosmoticpotentialinmicroorganismcell,NotonlyNH4^+butalsoNO3^-greatlyaffectedmethaneoxidation.Ureadidnotaffectmethaneoxidationinpaddysoilinthefirsttwodaysofincubation,butstronginhibitoryeffectwasobservedafterwards.Methanewasoxidizedinthetreatedsoilwithanoptimummoistureof280gkg^-1,andair-dryinginhibitedmethaneoxidationentirely.Theoptimumtemperatureofmethaneoxidationwasabout30℃inpaddysoil.whilenomethaneoxidationwasobservedat5℃or50℃。

简介：ThispaperdealswiththechemicalcomponentsandthechemicalstructureofligninofChinesefirandPoplarI-214fromplantationforest.Theresultsrevealedthatthecontentsofchemicalcomponentinheartwoodandsapwoodwerealmostthesameexceptethanol-benzeneextractbothinChinesefirandinPoplarI-214,Thecontentsofash,holocellulose,α-cellulose,pentosan,ethanol-benzeneextractandcold-waterextractinPoplarI-214werehigherthanthatinChinesefir,ThecontentoflignininPoplar...

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